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V4L/DVB (7492): vivi: Simplify the vivi driver and avoid deadlocks
vivi previously had a very complex queuing system and held spinlocks while doing copy_to_user, kmalloc, etc. This caused the driver to easily deadlock when a multi-threaded application used it and revealed bugs in videobuf too. This replaces the copy_to_user with memcpy since we were never copying to user space addresses. And makes the kmalloc atomic. Signed-off-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Brandon Philips
Mauro Carvalho Chehab
parent
aa9dbac426
commit
78718e5d44
@ -146,8 +146,6 @@ struct vivi_buffer {
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struct vivi_dmaqueue {
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struct list_head active;
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struct list_head queued;
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struct timer_list timeout;
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/* thread for generating video stream*/
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struct task_struct *kthread;
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@ -162,7 +160,6 @@ static LIST_HEAD(vivi_devlist);
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struct vivi_dev {
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struct list_head vivi_devlist;
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struct mutex lock;
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spinlock_t slock;
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struct mutex mutex;
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@ -323,24 +320,26 @@ static void gen_line(char *basep, int inipos, int wmax,
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end:
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return;
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}
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static void vivi_fillbuff(struct vivi_dev *dev, struct vivi_buffer *buf)
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{
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int h , pos = 0;
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int hmax = buf->vb.height;
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int wmax = buf->vb.width;
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struct timeval ts;
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char *tmpbuf = kmalloc(wmax * 2, GFP_KERNEL);
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char *tmpbuf = kmalloc(wmax * 2, GFP_ATOMIC);
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void *vbuf = videobuf_to_vmalloc(&buf->vb);
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if (!tmpbuf)
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return;
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if (!vbuf)
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return;
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for (h = 0; h < hmax; h++) {
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gen_line(tmpbuf, 0, wmax, hmax, h, dev->mv_count,
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dev->timestr);
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/* FIXME: replacing to __copy_to_user */
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if (copy_to_user(vbuf + pos, tmpbuf, wmax * 2) != 0)
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dprintk(dev, 2, "vivifill copy_to_user failed.\n");
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memcpy(vbuf + pos, tmpbuf, wmax * 2);
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pos += wmax*2;
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}
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@ -373,67 +372,58 @@ static void vivi_fillbuff(struct vivi_dev *dev, struct vivi_buffer *buf)
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dev->timestr, (unsigned long)tmpbuf, pos);
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/* Advice that buffer was filled */
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buf->vb.state = VIDEOBUF_DONE;
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buf->vb.field_count++;
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do_gettimeofday(&ts);
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buf->vb.ts = ts;
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list_del(&buf->vb.queue);
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wake_up(&buf->vb.done);
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buf->vb.state = VIDEOBUF_DONE;
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}
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static int restart_video_queue(struct vivi_dmaqueue *dma_q);
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static void vivi_thread_tick(struct vivi_dmaqueue *dma_q)
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static void vivi_thread_tick(struct vivi_fh *fh)
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{
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struct vivi_buffer *buf;
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struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
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struct vivi_buffer *buf;
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struct vivi_dev *dev = fh->dev;
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struct vivi_dmaqueue *dma_q = &dev->vidq;
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int bc;
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unsigned long flags = 0;
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spin_lock(&dev->slock);
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/* Announces videobuf that all went ok */
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for (bc = 0;; bc++) {
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if (list_empty(&dma_q->active)) {
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dprintk(dev, 1, "No active queue to serve\n");
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break;
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}
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dprintk(dev, 1, "Thread tick\n");
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buf = list_entry(dma_q->active.next,
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struct vivi_buffer, vb.queue);
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/* Nobody is waiting something to be done, just return */
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if (!waitqueue_active(&buf->vb.done)) {
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mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
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spin_unlock(&dev->slock);
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return;
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}
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do_gettimeofday(&buf->vb.ts);
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dprintk(dev, 2, "[%p/%d] wakeup\n", buf, buf->vb. i);
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/* Fill buffer */
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vivi_fillbuff(dev, buf);
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if (list_empty(&dma_q->active)) {
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del_timer(&dma_q->timeout);
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} else {
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mod_timer(&dma_q->timeout, jiffies + BUFFER_TIMEOUT);
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}
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spin_lock_irqsave(&dev->slock, flags);
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if (list_empty(&dma_q->active)) {
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dprintk(dev, 1, "No active queue to serve\n");
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goto unlock;
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}
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if (bc != 1)
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dprintk(dev, 1, "%s: %d buffers handled (should be 1)\n",
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__FUNCTION__, bc);
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spin_unlock(&dev->slock);
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buf = list_entry(dma_q->active.next,
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struct vivi_buffer, vb.queue);
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/* Nobody is waiting on this buffer, return */
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if (!waitqueue_active(&buf->vb.done))
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goto unlock;
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list_del(&buf->vb.queue);
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do_gettimeofday(&buf->vb.ts);
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/* Fill buffer */
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vivi_fillbuff(dev, buf);
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dprintk(dev, 1, "filled buffer %p\n", buf);
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wake_up(&buf->vb.done);
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dprintk(dev, 2, "[%p/%d] wakeup\n", buf, buf->vb. i);
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unlock:
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spin_unlock_irqrestore(&dev->slock, flags);
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return;
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}
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#define frames_to_ms(frames) \
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((frames * WAKE_NUMERATOR * 1000) / WAKE_DENOMINATOR)
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static void vivi_sleep(struct vivi_dmaqueue *dma_q)
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static void vivi_sleep(struct vivi_fh *fh)
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{
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struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
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int timeout, running_time;
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struct vivi_dev *dev = fh->dev;
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struct vivi_dmaqueue *dma_q = &dev->vidq;
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int timeout;
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DECLARE_WAITQUEUE(wait, current);
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dprintk(dev, 1, "%s dma_q=0x%08lx\n", __FUNCTION__,
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@ -443,37 +433,10 @@ static void vivi_sleep(struct vivi_dmaqueue *dma_q)
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if (kthread_should_stop())
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goto stop_task;
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running_time = jiffies - dma_q->ini_jiffies;
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dma_q->frame++;
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/* Calculate time to wake up */
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timeout = msecs_to_jiffies(frames_to_ms(dma_q->frame)) - running_time;
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timeout = msecs_to_jiffies(frames_to_ms(1));
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if (timeout > msecs_to_jiffies(frames_to_ms(2)) || timeout <= 0) {
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int old = dma_q->frame;
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int nframes;
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dma_q->frame = (jiffies_to_msecs(running_time) /
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frames_to_ms(1)) + 1;
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timeout = msecs_to_jiffies(frames_to_ms(dma_q->frame))
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- running_time;
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if (unlikely (timeout <= 0))
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timeout = 1;
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nframes = (dma_q->frame > old)?
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dma_q->frame - old : old - dma_q->frame;
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dprintk(dev, 1, "%ld: %s %d frames. "
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"Current frame is %d. Will sleep for %d jiffies\n",
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jiffies,
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(dma_q->frame > old)? "Underrun, losed" : "Overrun of",
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nframes, dma_q->frame, timeout);
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} else
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dprintk(dev, 1, "will sleep for %d jiffies\n", timeout);
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vivi_thread_tick(dma_q);
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vivi_thread_tick(fh);
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schedule_timeout_interruptible(timeout);
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@ -484,16 +447,15 @@ stop_task:
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static int vivi_thread(void *data)
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{
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struct vivi_dmaqueue *dma_q = data;
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struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
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struct vivi_fh *fh = data;
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struct vivi_dev *dev = fh->dev;
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dprintk(dev, 1, "thread started\n");
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mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
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set_freezable();
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for (;;) {
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vivi_sleep(dma_q);
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vivi_sleep(fh);
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if (kthread_should_stop())
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break;
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@ -502,16 +464,17 @@ static int vivi_thread(void *data)
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return 0;
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}
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static int vivi_start_thread(struct vivi_dmaqueue *dma_q)
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static int vivi_start_thread(struct vivi_fh *fh)
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{
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struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
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struct vivi_dev *dev = fh->dev;
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struct vivi_dmaqueue *dma_q = &dev->vidq;
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dma_q->frame = 0;
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dma_q->ini_jiffies = jiffies;
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dprintk(dev, 1, "%s\n", __FUNCTION__);
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dma_q->kthread = kthread_run(vivi_thread, dma_q, "vivi");
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dma_q->kthread = kthread_run(vivi_thread, fh, "vivi");
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if (IS_ERR(dma_q->kthread)) {
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printk(KERN_ERR "vivi: kernel_thread() failed\n");
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@ -536,91 +499,6 @@ static void vivi_stop_thread(struct vivi_dmaqueue *dma_q)
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}
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}
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static int restart_video_queue(struct vivi_dmaqueue *dma_q)
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{
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struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
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struct vivi_buffer *buf, *prev;
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dprintk(dev, 1, "%s dma_q=0x%08lx\n", __FUNCTION__,
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(unsigned long)dma_q);
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if (!list_empty(&dma_q->active)) {
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buf = list_entry(dma_q->active.next,
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struct vivi_buffer, vb.queue);
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dprintk(dev, 2, "restart_queue [%p/%d]: restart dma\n",
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buf, buf->vb.i);
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dprintk(dev, 1, "Restarting video dma\n");
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vivi_stop_thread(dma_q);
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/* cancel all outstanding capture / vbi requests */
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list_for_each_entry_safe(buf, prev, &dma_q->active, vb.queue) {
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list_del(&buf->vb.queue);
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buf->vb.state = VIDEOBUF_ERROR;
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wake_up(&buf->vb.done);
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}
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mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
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return 0;
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}
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prev = NULL;
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for (;;) {
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if (list_empty(&dma_q->queued))
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return 0;
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buf = list_entry(dma_q->queued.next,
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struct vivi_buffer, vb.queue);
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if (NULL == prev) {
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list_del(&buf->vb.queue);
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list_add_tail(&buf->vb.queue, &dma_q->active);
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dprintk(dev, 1, "Restarting video dma\n");
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vivi_stop_thread(dma_q);
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vivi_start_thread(dma_q);
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buf->vb.state = VIDEOBUF_ACTIVE;
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mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
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dprintk(dev, 2,
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"[%p/%d] restart_queue - first active\n",
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buf, buf->vb.i);
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} else if (prev->vb.width == buf->vb.width &&
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prev->vb.height == buf->vb.height &&
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prev->fmt == buf->fmt) {
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list_del(&buf->vb.queue);
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list_add_tail(&buf->vb.queue, &dma_q->active);
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buf->vb.state = VIDEOBUF_ACTIVE;
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dprintk(dev, 2,
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"[%p/%d] restart_queue - move to active\n",
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buf, buf->vb.i);
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} else {
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return 0;
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}
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prev = buf;
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}
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}
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static void vivi_vid_timeout(unsigned long data)
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{
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struct vivi_dev *dev = (struct vivi_dev *)data;
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struct vivi_dmaqueue *vidq = &dev->vidq;
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struct vivi_buffer *buf;
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spin_lock(&dev->slock);
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while (!list_empty(&vidq->active)) {
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buf = list_entry(vidq->active.next,
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struct vivi_buffer, vb.queue);
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list_del(&buf->vb.queue);
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buf->vb.state = VIDEOBUF_ERROR;
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wake_up(&buf->vb.done);
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printk(KERN_INFO "vivi/0: [%p/%d] timeout\n", buf, buf->vb.i);
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}
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restart_video_queue(vidq);
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spin_unlock(&dev->slock);
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}
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/* ------------------------------------------------------------------
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Videobuf operations
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------------------------------------------------------------------*/
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@ -649,13 +527,13 @@ static void free_buffer(struct videobuf_queue *vq, struct vivi_buffer *buf)
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struct vivi_fh *fh = vq->priv_data;
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struct vivi_dev *dev = fh->dev;
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dprintk(dev, 1, "%s\n", __FUNCTION__);
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dprintk(dev, 1, "%s, state: %i\n", __FUNCTION__, buf->vb.state);
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if (in_interrupt())
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BUG();
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videobuf_waiton(&buf->vb, 0, 0);
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videobuf_vmalloc_free(&buf->vb);
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dprintk(dev, 1, "free_buffer: freed");
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buf->vb.state = VIDEOBUF_NEEDS_INIT;
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}
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@ -668,28 +546,25 @@ buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
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struct vivi_fh *fh = vq->priv_data;
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struct vivi_dev *dev = fh->dev;
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struct vivi_buffer *buf = container_of(vb, struct vivi_buffer, vb);
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int rc, init_buffer = 0;
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int rc;
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dprintk(dev, 1, "%s, field=%d\n", __FUNCTION__, field);
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BUG_ON(NULL == fh->fmt);
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if (fh->width < 48 || fh->width > norm_maxw() ||
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fh->height < 32 || fh->height > norm_maxh())
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return -EINVAL;
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buf->vb.size = fh->width*fh->height*2;
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if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
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return -EINVAL;
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if (buf->fmt != fh->fmt ||
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buf->vb.width != fh->width ||
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buf->vb.height != fh->height ||
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buf->vb.field != field) {
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buf->fmt = fh->fmt;
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buf->vb.width = fh->width;
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buf->vb.height = fh->height;
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buf->vb.field = field;
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init_buffer = 1;
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}
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/* These properties only change when queue is idle, see s_fmt */
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buf->fmt = fh->fmt;
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buf->vb.width = fh->width;
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buf->vb.height = fh->height;
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buf->vb.field = field;
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if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
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rc = videobuf_iolock(vq, &buf->vb, NULL);
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@ -712,45 +587,12 @@ buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
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struct vivi_buffer *buf = container_of(vb, struct vivi_buffer, vb);
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struct vivi_fh *fh = vq->priv_data;
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struct vivi_dev *dev = fh->dev;
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struct vivi_dmaqueue *vidq = &dev->vidq;
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struct vivi_buffer *prev;
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struct vivi_dmaqueue *vidq = &dev->vidq;
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if (!list_empty(&vidq->queued)) {
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dprintk(dev, 1, "adding vb queue=0x%08lx\n",
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(unsigned long)&buf->vb.queue);
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list_add_tail(&buf->vb.queue, &vidq->queued);
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buf->vb.state = VIDEOBUF_QUEUED;
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dprintk(dev, 2, "[%p/%d] buffer_queue - append to queued\n",
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buf, buf->vb.i);
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} else if (list_empty(&vidq->active)) {
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list_add_tail(&buf->vb.queue, &vidq->active);
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dprintk(dev, 1, "%s\n", __FUNCTION__);
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buf->vb.state = VIDEOBUF_ACTIVE;
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mod_timer(&vidq->timeout, jiffies+BUFFER_TIMEOUT);
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dprintk(dev, 2, "[%p/%d] buffer_queue - first active\n",
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buf, buf->vb.i);
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vivi_start_thread(vidq);
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} else {
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prev = list_entry(vidq->active.prev,
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struct vivi_buffer, vb.queue);
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if (prev->vb.width == buf->vb.width &&
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prev->vb.height == buf->vb.height &&
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prev->fmt == buf->fmt) {
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list_add_tail(&buf->vb.queue, &vidq->active);
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buf->vb.state = VIDEOBUF_ACTIVE;
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dprintk(dev, 2,
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"[%p/%d] buffer_queue - append to active\n",
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buf, buf->vb.i);
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} else {
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list_add_tail(&buf->vb.queue, &vidq->queued);
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buf->vb.state = VIDEOBUF_QUEUED;
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dprintk(dev, 2,
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"[%p/%d] buffer_queue - first queued\n",
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buf, buf->vb.i);
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}
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}
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buf->vb.state = VIDEOBUF_QUEUED;
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list_add_tail(&buf->vb.queue, &vidq->active);
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}
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static void buffer_release(struct videobuf_queue *vq,
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@ -759,12 +601,9 @@ static void buffer_release(struct videobuf_queue *vq,
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struct vivi_buffer *buf = container_of(vb, struct vivi_buffer, vb);
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struct vivi_fh *fh = vq->priv_data;
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struct vivi_dev *dev = (struct vivi_dev *)fh->dev;
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struct vivi_dmaqueue *vidq = &dev->vidq;
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dprintk(dev, 1, "%s\n", __FUNCTION__);
|
||||
|
||||
vivi_stop_thread(vidq);
|
||||
|
||||
free_buffer(vq, buf);
|
||||
}
|
||||
|
||||
@ -870,17 +709,31 @@ static int vidioc_s_fmt_cap(struct file *file, void *priv,
|
||||
struct v4l2_format *f)
|
||||
{
|
||||
struct vivi_fh *fh = priv;
|
||||
struct videobuf_queue *q = &fh->vb_vidq;
|
||||
|
||||
int ret = vidioc_try_fmt_cap(file, fh, f);
|
||||
if (ret < 0)
|
||||
return (ret);
|
||||
|
||||
mutex_lock(&q->vb_lock);
|
||||
|
||||
if (videobuf_queue_is_busy(&fh->vb_vidq)) {
|
||||
dprintk(fh->dev, 1, "%s queue busy\n", __FUNCTION__);
|
||||
ret = -EBUSY;
|
||||
goto out;
|
||||
}
|
||||
|
||||
fh->fmt = &format;
|
||||
fh->width = f->fmt.pix.width;
|
||||
fh->height = f->fmt.pix.height;
|
||||
fh->vb_vidq.field = f->fmt.pix.field;
|
||||
fh->type = f->type;
|
||||
|
||||
return (0);
|
||||
ret = 0;
|
||||
out:
|
||||
mutex_unlock(&q->vb_lock);
|
||||
|
||||
return (ret);
|
||||
}
|
||||
|
||||
static int vidioc_reqbufs(struct file *file, void *priv,
|
||||
@ -1097,6 +950,8 @@ unlock:
|
||||
NULL, &dev->slock, fh->type, V4L2_FIELD_INTERLACED,
|
||||
sizeof(struct vivi_buffer), fh);
|
||||
|
||||
vivi_start_thread(fh);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -1252,18 +1107,12 @@ static int __init vivi_init(void)
|
||||
|
||||
/* init video dma queues */
|
||||
INIT_LIST_HEAD(&dev->vidq.active);
|
||||
INIT_LIST_HEAD(&dev->vidq.queued);
|
||||
init_waitqueue_head(&dev->vidq.wq);
|
||||
|
||||
/* initialize locks */
|
||||
mutex_init(&dev->lock);
|
||||
spin_lock_init(&dev->slock);
|
||||
mutex_init(&dev->mutex);
|
||||
|
||||
dev->vidq.timeout.function = vivi_vid_timeout;
|
||||
dev->vidq.timeout.data = (unsigned long)dev;
|
||||
init_timer(&dev->vidq.timeout);
|
||||
|
||||
vfd = video_device_alloc();
|
||||
if (NULL == vfd)
|
||||
break;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user